ManagedRoute uses ioctl to add/remove routes on Linux

Added LinuxNetLink to talk to the rtnetlink socket for adding interfaces, addresses routes.  Not yet complete.  Can currently monitor changes on the system.

1 files changed, 149 insertions, 14 deletions

diff --git a/osdep/ManagedRoute.cpp b/osdep/ManagedRoute.cpp
index d7c80704..8d64fde3 100644
--- a/osdep/ManagedRoute.cpp
+++ b/osdep/ManagedRoute.cpp
@@ -48,6 +48,13 @@
 #include <arpa/inet.h>
 #include <net/route.h>
 #include <net/if.h>
+#ifdef __LINUX__
+#include <sys/ioctl.h>
+#include <bits/sockaddr.h>
+#include <asm/types.h>
+#include <linux/rtnetlink.h>
+#include <sys/socket.h>
+#endif
 #ifdef __BSD__
 #include <net/if_dl.h>
 #include <sys/sysctl.h>
@@ -277,27 +284,155 @@ static void _routeCmd(const char *op,const InetAddress &target,const InetAddress
 #ifdef __LINUX__ // ----------------------------------------------------------
 #define ZT_ROUTING_SUPPORT_FOUND 1
 
-static void _routeCmd(const char *op,const InetAddress &target,const InetAddress &via,const char *localInterface)
+static bool _hasRoute(const InetAddress &target, const InetAddress &via, const char *localInterface)
 {
-	long p = (long)fork();
-	if (p > 0) {
-		int exitcode = -1;
-		::waitpid(p,&exitcode,0);
-	} else if (p == 0) {
-		::close(STDOUT_FILENO);
-		::close(STDERR_FILENO);
-		char ipbuf[64],ipbuf2[64];
+	if (target.ss_family == AF_INET) {
+		int fd = socket(AF_NETLINK, SOCK_RAW, NETLINK_ROUTE);
+
+		char *buf;
+		int nll;
+		struct rtmsg *rtp;
+		int rtl;
+		struct rtattr *rtap;
+
+		struct sockaddr_nl la;
+		bzero(&la, sizeof(la));
+		la.nl_family = AF_NETLINK;
+		la.nl_pad = 0;
+		la.nl_pid = (uint32_t)((ptrdiff_t)&target % getpid());
+		la.nl_groups = 0;
+		int rtn = bind(fd, (struct sockaddr*)&la, sizeof(la));
+
+
+
+		close(fd);
+		return false;
+	} else {
+
+		return false;
+	}
+}
+
+
+static void _routeCmd(const char *op, const InetAddress &target, const InetAddress &via, const char *localInterface) 
+{
+	bool hasRoute = _hasRoute(target, via, localInterface);
+	if (hasRoute && (strcmp(op, "add") == 0 || strcmp(op, "replace") == 0)) {
+		return;
+	} else if (!hasRoute && (strcmp(op, "remove") == 0 || strcmp(op, "del") == 0)) {
+		return;
+	}
+
+	char targetStr[64] = {0};
+	char viaStr[64] = {0};
+	InetAddress nmsk = target.netmask();
+	char nmskStr[64] = {0};
+	fprintf(stderr, "Received Route Cmd: %s target: %s via: %s netmask: %s localInterface: %s\n", op, target.toString(targetStr), via.toString(viaStr), nmsk.toString(nmskStr), localInterface);
+
+	int fd = socket(PF_INET, SOCK_DGRAM, IPPROTO_IP);;
+	struct rtentry route = {0};
+
+	if (target.ss_family == AF_INET) {
+		struct sockaddr_in *target_in = (struct sockaddr_in*)&target;
+		struct sockaddr_in *via_in = (struct sockaddr_in*)&via;
+		InetAddress netmask = target.netmask();
+		struct sockaddr_in *netmask_in = (struct sockaddr_in*)&netmask;
+
+		struct sockaddr_in *addr = NULL;
+
+		// set target
+		addr = (struct sockaddr_in *)&route.rt_dst;
+		addr->sin_family = AF_INET;
+		addr->sin_addr = target_in->sin_addr;
+
+		// set netmask
+		addr = (struct sockaddr_in *)&route.rt_genmask;
+		addr->sin_family = AF_INET;
+		addr->sin_addr = netmask_in->sin_addr;
+
+		route.rt_dev = const_cast<char*>(localInterface);
+
 		if (via) {
-			::execl(ZT_LINUX_IP_COMMAND,ZT_LINUX_IP_COMMAND,(target.ss_family == AF_INET6) ? "-6" : "-4","route",op,target.toString(ipbuf),"via",via.toIpString(ipbuf2),(const char *)0);
-			::execl(ZT_LINUX_IP_COMMAND_2,ZT_LINUX_IP_COMMAND_2,(target.ss_family == AF_INET6) ? "-6" : "-4","route",op,target.toString(ipbuf),"via",via.toIpString(ipbuf2),(const char *)0);
+			// set the gateway
+			addr = (struct sockaddr_in *)&route.rt_gateway;
+			addr->sin_family = AF_INET;
+			addr->sin_addr = via_in->sin_addr;
+
+			route.rt_flags = RTF_UP | RTF_GATEWAY;
 		} else if ((localInterface)&&(localInterface[0])) {
-			::execl(ZT_LINUX_IP_COMMAND,ZT_LINUX_IP_COMMAND,(target.ss_family == AF_INET6) ? "-6" : "-4","route",op,target.toString(ipbuf),"dev",localInterface,(const char *)0);
-			::execl(ZT_LINUX_IP_COMMAND_2,ZT_LINUX_IP_COMMAND_2,(target.ss_family == AF_INET6) ? "-6" : "-4","route",op,target.toString(ipbuf),"dev",localInterface,(const char *)0);
+			route.rt_flags = RTF_UP;//| RTF_HOST;
+		}
+	}
+	else if (target.ss_family == AF_INET6) 
+	{
+		struct sockaddr_in6 *addr = NULL;
+
+		// set target
+		addr = (struct sockaddr_in6 *)&route.rt_dst;
+		addr->sin6_family = AF_INET6;
+		memcpy(&addr->sin6_addr, &((struct sockaddr_in6*)&target)->sin6_addr, sizeof(struct in6_addr));
+
+		//set netmask
+		addr = (struct sockaddr_in6 *)&route.rt_genmask;
+		addr->sin6_family = AF_INET6;
+		InetAddress netmask = target.netmask();
+		memcpy(&addr->sin6_addr, &((struct sockaddr_in6*)&netmask)->sin6_addr, sizeof(struct in6_addr));
+
+		if (via) {
+			// set the gateway
+			addr = (struct sockaddr_in6*)&route.rt_gateway;
+			addr->sin6_family = AF_INET;
+			memcpy(&addr->sin6_addr, &((struct sockaddr_in6*)&via)->sin6_addr, sizeof(struct in6_addr));
+
+			route.rt_flags = RTF_UP | RTF_GATEWAY;
+		} else if ((localInterface)&&(localInterface[0])) {
+			route.rt_dev = const_cast<char*>(localInterface);
+			route.rt_flags = RTF_UP;
 		}
-		::_exit(-1);
 	}
+
+	unsigned long ctl = -1;
+	if (strcmp(op, "add") == 0 || strcmp(op, "replace") == 0) {
+		ctl = SIOCADDRT;
+	} else if (strcmp(op, "remove") == 0 || strcmp(op, "del") == 0) {
+		ctl = SIOCDELRT;
+	} else {
+		close(fd);
+		return;
+	}
+
+	if ( ioctl(fd, ctl, &route)) {
+		fprintf(stderr, "Error adding route: %s\n", strerror(errno));
+		close(fd);
+		::exit(1);
+	}
+	close(fd);
 }
 
+// static void _routeCmd(const char *op,const InetAddress &target,const InetAddress &via,const char *localInterface)
+// {
+// 	// long p = (long)fork();
+// 	// if (p > 0) {
+// 	// 	int exitcode = -1;
+// 	// 	::waitpid(p,&exitcode,0);
+// 	// } else if (p == 0) {
+// 	// 	::close(STDOUT_FILENO);
+// 	// 	::close(STDERR_FILENO);
+// 		char ipbuf[64],ipbuf2[64];
+
+		
+
+// 		if (via) {
+// 			::execl(ZT_LINUX_IP_COMMAND,ZT_LINUX_IP_COMMAND,(target.ss_family == AF_INET6) ? "-6" : "-4","route",op,target.toString(ipbuf),"via",via.toIpString(ipbuf2),(const char *)0);
+// 			::execl(ZT_LINUX_IP_COMMAND_2,ZT_LINUX_IP_COMMAND_2,(target.ss_family == AF_INET6) ? "-6" : "-4","route",op,target.toString(ipbuf),"via",via.toIpString(ipbuf2),(const char *)0);
+// 		} else if ((localInterface)&&(localInterface[0])) {
+// 			::execl(ZT_LINUX_IP_COMMAND,ZT_LINUX_IP_COMMAND,(target.ss_family == AF_INET6) ? "-6" : "-4","route",op,target.toString(ipbuf),"dev",localInterface,(const char *)0);
+// 			::execl(ZT_LINUX_IP_COMMAND_2,ZT_LINUX_IP_COMMAND_2,(target.ss_family == AF_INET6) ? "-6" : "-4","route",op,target.toString(ipbuf),"dev",localInterface,(const char *)0);
+// 		}
+// 	// 	::_exit(-1);
+// 	// }
+// }
+
 #endif // __LINUX__ ----------------------------------------------------------
 
 #ifdef __WINDOWS__ // --------------------------------------------------------